Research for ASVAB

This research memorandum examines the validity of the Armed Services Vocational Aptitude Battery (ASVAB) against several measures of infantry performance collected as part of Job Performance Measurement project. ASVAB was highly related to hands-on performance of critical infantry tasks, written infantry job knowledge tests, and grades in initial infantry training courses. The validity of ASVAB was also found to extend into the second term of service by being able to predict the performance of infantry unit leaders.

The Armed Services Vocational Aptitude Battery (ASVAB) is highly oriented to math and verbal content areas. New predictor tests that are unique relative to the current ASVAB subtests may have potential for improving predictive validity. The purpose of this research memorandum is to investigate the incremental validity of several new tests that were administered as part of the Marine Corps Job Performance Measurement project for the infantry occupational field.

Statistical work connected with the computerized adaptive testing version of the Armed Services Vocational Aptitude Battery often involves the density and cumulative functions of the normal distribution, and the logistic function. In long, iterative calculations, computation of these functions can be time consuming. This research memorandum presents piecewise linear and cubic approximations for the normal cumulative distribution function, the logistic function, and the normal density function. The approximations are as accurate as library functions, and much faster in computing speed.

New kinds of tests are being evaluated as potential additions to the Armed Services Vocational Aptitude Battery (ASVAB). They are compared on the basis of the criterion variance they explain when added to the ASVAB. The evaluation may use scores on the ASVAB given during enlistment processing, or a new ASVAB may be administered concurrently with the new tests. This paper compares these two research designs in terms of their effect on evaluation of new tests. The analysis uses Infantry data from the Marine Corps' Job Performance Measurement project, in which concurrent as well as enlistment ASVAB scores are available. While lower increments in explained variances are obtained when the ASVAB is concurrent, the difference between the administrations is small compared to variations across criterion variables and occupational areas.